Communication system often contains two interface cards to provide transceiver functions over a medium, such as a coaxial cable. The two cards include a primary card 101 and a protection card 102, see FIG. 1. The primary card 101 contains a medium control switch 103, which couples/decouples its transceiver to a communication medium 105. Protection card 102 also contains a medium control switch 104, which couples/decouples its transceiver to the telecommunication medium 105. Under normal operating conditions, the medium control switch 103 is ON and the primary card is coupled to the communication medium and performs communication functions. The protection card is in a “hot” standby mode with its medium control switch 104 turned OFF.
As soon as a management card has determined a failure on the primary card, switch 103 is turned OFF and switch 104 is turned ON. The protection card then takes over communication traffic. The primary and protection cards are typically located physically distanced one from another. As such, the communication medium, such as a coaxial cable, is split into two cables 106 and 107. While cable 106 is connected to transceiver 101 through switch 103 and is properly terminated, cable 107 is floating because switch 104 is OFF. Because cards 101 and 102 are two separate entities, floating cable 107 must have some length, that causes reflection of signal back into communication medium 105. This can cause data transfer errors because the communication signals in the medium 105 get distorted.
To reduce reflection to a sustainable level, the maximum length of the floating cable is limited. This limitation, however, restricts the design of the interface cards. As bandwidth of the signal in the cable gets wider, the length of the floating cable must decrease. Because the floating cable cannot have a zero length, the data rate of the communication equipment is limited.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a more flexible interface card for communication system.